patches-3.6.3-rt7.tar.xzv3.6.3-rt7

md5sum:
8c808f787c8afa3859023cb2afd087c0  patches-3.6.3-rt7.tar.xz

Announce:
 ----------------
 Dear RT Folks,

 I'm pleased to announce the 3.6.3-rt7 release.

 Changes since 3.6.3-rt6:

    * Enable SLUB for RT

      Last time I looked at SLUB for RT (some years ago) it was just
      way more painful than dealing with SLAB, but Christoph Lameter
      has done major surgery on the SLUB code since then and it turns
      out that making SLUB usable for RT has become very simple. Thanks
      Christoph!

       slab.c: 172 insertions(+), 58 deletions(-)
       slub.c:  17 insertions(+), 13 deletions(-)

      I did some quick comparisons and even a simple hackbench run
      shows a significant speedup with SLUB vs. SLAB on RT. I'm not too
      surprised as SLUBs fastpath does not have the RT induced
      contention problems which we can observe with SLAB.

      As usual, give it a good testing and report whatever explodes :)

 The delta patch against 3.6.3-rt6 is appended below and can be found
 here:

   http://www.kernel.org/pub/linux/kernel/projects/rt/3.6/incr/patch-3.6.3-rt6-rt7.patch.xz

 The RT patch against 3.6.3 can be found here:

   http://www.kernel.org/pub/linux/kernel/projects/rt/3.6/patch-3.6.3-rt7.patch.xz

 The split quilt queue is available at:

   http://www.kernel.org/pub/linux/kernel/projects/rt/3.6/patches-3.6.3-rt7.tar.xz

 Enjoy,

 	tglx

 [delta patch snipped]
 ----------------

http://marc.info/?l=linux-rt-users&m=135127757519113&w=2

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

3 files changed, 153 insertions, 1 deletions

diff --git a/localversion.patch b/localversion.patch
index 04bbef2..247957a 100644
--- a/localversion.patch
+++ b/localversion.patch
@@ -14,4 +14,4 @@ Index: linux-stable/localversion-rt
 --- /dev/null
 +++ linux-stable/localversion-rt
 @@ -0,0 +1 @@
-+-rt6
++-rt7
diff --git a/mm-enable-slub.patch b/mm-enable-slub.patch
new file mode 100644
index 0000000..8797b71
--- /dev/null
+++ b/mm-enable-slub.patch
@@ -0,0 +1,151 @@
+Subject: mm: Enable SLUB for RT
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Thu, 25 Oct 2012 10:32:35 +0100
+
+Make SLUB RT aware and remove the restriction in Kconfig.
+
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+---
+ init/Kconfig |    1 -
+ mm/slub.c    |   30 +++++++++++++++++-------------
+ 2 files changed, 17 insertions(+), 14 deletions(-)
+
+Index: linux-3.6/init/Kconfig
+===================================================================
+--- linux-3.6.orig/init/Kconfig
++++ linux-3.6/init/Kconfig
+@@ -1442,7 +1442,6 @@ config SLAB
+ 
+ config SLUB
+ 	bool "SLUB (Unqueued Allocator)"
+-	depends on !PREEMPT_RT_FULL
+ 	help
+ 	   SLUB is a slab allocator that minimizes cache line usage
+ 	   instead of managing queues of cached objects (SLAB approach).
+Index: linux-3.6/mm/slub.c
+===================================================================
+--- linux-3.6.orig/mm/slub.c
++++ linux-3.6/mm/slub.c
+@@ -31,6 +31,7 @@
+ #include <linux/fault-inject.h>
+ #include <linux/stacktrace.h>
+ #include <linux/prefetch.h>
++#include <linux/locallock.h>
+ 
+ #include <trace/events/kmem.h>
+ 
+@@ -225,6 +226,8 @@ static inline void stat(const struct kme
+ #endif
+ }
+ 
++static DEFINE_LOCAL_IRQ_LOCK(slub_lock);
++
+ /********************************************************************
+  * 			Core slab cache functions
+  *******************************************************************/
+@@ -1278,7 +1281,7 @@ static struct page *allocate_slab(struct
+ 	flags &= gfp_allowed_mask;
+ 
+ 	if (flags & __GFP_WAIT)
+-		local_irq_enable();
++		local_unlock_irq(slub_lock);
+ 
+ 	flags |= s->allocflags;
+ 
+@@ -1318,7 +1321,7 @@ static struct page *allocate_slab(struct
+ 	}
+ 
+ 	if (flags & __GFP_WAIT)
+-		local_irq_disable();
++		local_lock_irq(slub_lock);
+ 	if (!page)
+ 		return NULL;
+ 
+@@ -1959,9 +1962,9 @@ int put_cpu_partial(struct kmem_cache *s
+ 				 * partial array is full. Move the existing
+ 				 * set to the per node partial list.
+ 				 */
+-				local_irq_save(flags);
++				local_lock_irqsave(slub_lock, flags);
+ 				unfreeze_partials(s);
+-				local_irq_restore(flags);
++				local_unlock_irqrestore(slub_lock, flags);
+ 				pobjects = 0;
+ 				pages = 0;
+ 				stat(s, CPU_PARTIAL_DRAIN);
+@@ -2201,7 +2204,7 @@ static void *__slab_alloc(struct kmem_ca
+ 	struct page *page;
+ 	unsigned long flags;
+ 
+-	local_irq_save(flags);
++	local_lock_irqsave(slub_lock, flags);
+ #ifdef CONFIG_PREEMPT
+ 	/*
+ 	 * We may have been preempted and rescheduled on a different
+@@ -2262,7 +2265,7 @@ load_freelist:
+ 	VM_BUG_ON(!c->page->frozen);
+ 	c->freelist = get_freepointer(s, freelist);
+ 	c->tid = next_tid(c->tid);
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(slub_lock, flags);
+ 	return freelist;
+ 
+ new_slab:
+@@ -2281,7 +2284,7 @@ new_slab:
+ 		if (!(gfpflags & __GFP_NOWARN) && printk_ratelimit())
+ 			slab_out_of_memory(s, gfpflags, node);
+ 
+-		local_irq_restore(flags);
++		local_unlock_irqrestore(slub_lock, flags);
+ 		return NULL;
+ 	}
+ 
+@@ -2296,7 +2299,7 @@ new_slab:
+ 	deactivate_slab(s, page, get_freepointer(s, freelist));
+ 	c->page = NULL;
+ 	c->freelist = NULL;
+-	local_irq_restore(flags);
++	local_unlock_irqrestore(slub_lock, flags);
+ 	return freelist;
+ }
+ 
+@@ -2488,7 +2491,8 @@ static void __slab_free(struct kmem_cach
+ 				 * Otherwise the list_lock will synchronize with
+ 				 * other processors updating the list of slabs.
+ 				 */
+-				spin_lock_irqsave(&n->list_lock, flags);
++				local_spin_lock_irqsave(slub_lock,
++							&n->list_lock, flags);
+ 
+ 			}
+ 		}
+@@ -2538,7 +2542,7 @@ static void __slab_free(struct kmem_cach
+ 			stat(s, FREE_ADD_PARTIAL);
+ 		}
+ 	}
+-	spin_unlock_irqrestore(&n->list_lock, flags);
++	local_spin_unlock_irqrestore(slub_lock, &n->list_lock, flags);
+ 	return;
+ 
+ slab_empty:
+@@ -2552,7 +2556,7 @@ slab_empty:
+ 		/* Slab must be on the full list */
+ 		remove_full(s, page);
+ 
+-	spin_unlock_irqrestore(&n->list_lock, flags);
++	local_spin_unlock_irqrestore(slub_lock, &n->list_lock, flags);
+ 	stat(s, FREE_SLAB);
+ 	discard_slab(s, page);
+ }
+@@ -4002,9 +4006,9 @@ static int __cpuinit slab_cpuup_callback
+ 	case CPU_DEAD_FROZEN:
+ 		mutex_lock(&slab_mutex);
+ 		list_for_each_entry(s, &slab_caches, list) {
+-			local_irq_save(flags);
++			local_lock_irqsave(slub_lock, flags);
+ 			__flush_cpu_slab(s, cpu);
+-			local_irq_restore(flags);
++			local_unlock_irqrestore(slub_lock, flags);
+ 		}
+ 		mutex_unlock(&slab_mutex);
+ 		break;
diff --git a/series b/series
index e128100..43a7ac7 100644
--- a/series
+++ b/series
@@ -597,6 +597,7 @@ softirq-split-locks.patch
 
 # Enable full RT
 rcu-tiny-solve-rt-mistery.patch
+mm-enable-slub.patch
 kconfig-disable-a-few-options-rt.patch
 kconfig-preempt-rt-full.patch
 #rt-replace-rt-spin-lock-to-raw-one-in-res_counter.patch